Comparative Analysis of Industrial Codes for Spherical Shells Under External Pressure

This study evaluates the precision of Industrial Design Codes for the buckling of externally pressurized spherical shells, identifying the most accurate code for current applications. Industrial standards such as the European Convention for Constructional Steelwork (ECCS), Det Norske Veritas (DNV), PD 5500 and the American Bureau of Shipping (ABS) offer different buckling classifications, but their reliability requires further validation. A comparative analysis was conducted by computing buckling pressure values from all four design codes and comparing them with experimental results. Further screening was performed within a mean value range of 0.75 ≤ µ ≤ 1.2, with reliability assessments based on statistical mean bias (Xₘ) and the correlation coefficient (ρ). Uncertainty and sensitivity analyses were also conducted for thin-walled pressure vessels. Results indicate DNV exhibits the highest accuracy for thick shells (70% alignment with a mean value of 0.9827, ρ = 0.9964), PD 5500 shows 51% accuracy for moderate shells (mean 0.9852), and ABS offers superior precision for thin shells (mean 1.0611). Monte Carlo simulations reveal thickness variability as the most significant factor (CV = 11.35%). This study enhances the reliability of industrial design codes, contributing to improved theoretical models and design methodologies.